On Tue, 2005-05-17 at 09:37 -0500, Johnny Hughes wrote:
> On Tue, 2005-05-17 at 07:28 -0700, Lee Parmeter wrote:
> > I started the named server on CentOS and it seems to
> > resolve DNS request OK, but it does not seem to retain the
> > info for very long. From what I can tell using "dig", a
> > domain's ip address is retained for less than 12 hours. So
> > in the morning, it takes 4+ seconds to resolve again the
> > first time. Is there an adjustment somewhere for this or is
> > the caching named support not enabled by default?
> >
> > Also, I thought it would be faster if I set named to use my
> > ISP's named server as the first choice. Where do I set this
> > up, in root.hints?
> >
> > Anyone who knows more about "named" please feel free to
> > comment!
> >
> > Thanks!
> > Lee
> >
>
> The owner of the domain controls how long DNS entries are cached. If
> you do a dig, one of the things you get from an authorized DNS server
> for that domain is the TTL (time-to-live). That is how many seconds
> your entry will remained cached in a non-authoritative DNS server.
>
> for example:
> -------------------------------------------------------------------
> dig www.yahoo.com
>
> ; <<>> DiG 9.2.4 <<>> www.yahoo.com
> ;; global options: printcmd
> ;; Got answer:
> ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 2270
> ;; flags: qr rd ra; QUERY: 1, ANSWER: 9, AUTHORITY: 10, ADDITIONAL: 2
>
> ;; QUESTION SECTION:
> ;www.yahoo.com. IN A
>
> ;; ANSWER SECTION:
> www.yahoo.com. 300 IN CNAME www.yahoo.akadns.net.
> www.yahoo.akadns.net. 60 IN A 68.142.197.89
> www.yahoo.akadns.net. 60 IN A 68.142.197.90
> www.yahoo.akadns.net. 60 IN A 68.142.197.73
> www.yahoo.akadns.net. 60 IN A 68.142.197.75
> www.yahoo.akadns.net. 60 IN A 68.142.197.76
> www.yahoo.akadns.net. 60 IN A 68.142.197.80
> www.yahoo.akadns.net. 60 IN A 68.142.197.83
> www.yahoo.akadns.net. 60 IN A 68.142.197.88
>
> ;; AUTHORITY SECTION:
> akadns.net. 127047 IN NS asia5.akadns.net.
> akadns.net. 127047 IN NS asia9.akadns.net.
> akadns.net. 127047 IN NS eur10.akadns.net.
> akadns.net. 127047 IN NS za.akadns.org.
> akadns.net. 127047 IN NS zh.akadns.org.
> akadns.net. 127047 IN NS eur3.akadns.net.
> akadns.net. 127047 IN NS use1.akadns.net.
> akadns.net. 127047 IN NS use9.akadns.net.
> akadns.net. 127047 IN NS usw6.akadns.net.
> akadns.net. 127047 IN NS usw7.akadns.net.
>
> ;; ADDITIONAL SECTION:
> za.akadns.org. 526 IN A 208.185.132.176
> zh.akadns.org. 526 IN A 63.208.48.46
>
> ;; Query time: 164 msec
> ;; SERVER: 192.168.0.2#53(192.168.0.2)
> ;; WHEN: Tue May 17 09:35:27 2005
> ;; MSG SIZE rcvd: 424
> ---------------------------------------------------------------
>
> So that will remain in cache another 127047 seconds :)
> _______________________________________________
oops ... I was wrong ... for 300 seconds :)
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